experimental: the :pop and :win32 pseudolayers

Okay, final email about perlexperiment for the night.
The :pop and :win32 pseudolayers are listed as experimental. 5.14 introduced
some fixes for :pop. Is it still an experiment, keeping in mind that PerlIO is
*not*?
I can't find much about the history of these layers in a quick search.
--
rjbs